So that is pretty much all about it, if you want you can click Close when you don’t want them anymore or click Open in a new window, this will open another tab to the Gmail help site where you can find more details about every keyboard shortcut for Gmail and if you want you can print them out. Remember, if when you are trying Shift + ? doesn’t work, you may have Keyboard shortcuts feature disable in your Gmail settings. To fix this go to your Gmail settings page, while in the General tab, select Keyboard shortcuts on, then scroll down the page and click Save changes.
I hope this helps a little when you are using Gmail. If you have any question let me know in the comment section below. All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.